close all
u=[-1; 2];
v=[-3; -1];

o = [0; 0];  %# Origin
ceuArrow(o,u,'b',2);
text(u(1)-0.15,u(2)+0.2,'u','Fontsize',14)
axis([-6 8 -2 5])
axis square
grid on
hold on
xlabel('x_1')
ylabel('x_2')
ceuArrow(o,v,'r',2);
text(v(1)-0.15,v(2)-0.15,'v','Fontsize',14)
ceuArrow(o,-v,'k',2);
text(-v(1)+0.15,-v(2)-0.15,'-v','Fontsize',14)
ceuArrow(o,-2*v,'k',2);
text(-2*v(1)+0.15,-2*v(2)+0.15,'-2v','Fontsize',14)
u_v=u+v;
ceuArrow(o,u_v,'k',2);
text(u_v(1)+0.15,u_v(2)+0.15,'u+v','Fontsize',14)
u_v=u-v;
ceuArrow(o,u_v,'k',2);
text(u_v(1)+0.15,u_v(2)+0.15,'u-v','Fontsize',14)
u_v=u-2*v;
ceuArrow(o,u_v,'k',2);
text(u_v(1)+0.15,u_v(2)+0.15,'u-2v','Fontsize',14)

